When sourcing for commercial or retail purposes, material selection dictates both durability and safety. For metal bunk beds, ensure the use of cold-rolled steel with a tube thickness of at least 1.2mm to 1.5mm to prevent bending. For wooden bunk beds, prioritize solid pine, rubberwood, or birch over MDF to ensure structural integrity. Always verify that the surface coating is non-toxic, such as lead-free powder coating for metal or water-based paint for wood, to meet international health standards.